Sosigenes of Alexandria

Sosigenes of Alexandria (died 31 BC) was a Greek astronomer and the tutor and adviser of Queen Cleopatra of Egypt. Sosigenes was one of her closest confidants, and he also served as an envoy to the Roman Republic on many occasions. In 31 BC, he was publicly murdered by the Roman caesar Octavian in the Roman forum to announce the start of war with Egypt.

Biography
Sosigenes of Alexandria was a learned Greek astronomer, and he was employed as a tutor and adviser to Queen Cleopatra of Egypt. Sosigenes educated Cleopatra on philosophy, poetry, astronomy, and other fields of science and social science, and he was so wise that Julius Caesar consulted him to assist him with creating the Julian calendar for the Roman Republic. Sosigenes would also serve as an envoy for Cleopatra during her negotiations with Mark Antony, and he was sent to Rome on many occasions. In 31 BC, after the discovery that Antony's will included him being buried in his "beloved Alexandria", the Roman Senate unanimously called for war against Egypt, and Octavian took up a war javelin and marched out of the Senate with the other senators, crying "war". He proceeded to ask the people of the crowded forum where Egypt was; he corrected them by pointing at Sosigenes, who walked towards Octavian as the crowd backed away. Octavian proceeded to throw the javelin at Sosigenes, commencing his war with Egypt.